Proper Use

Sulfonamides should not be given to infants less than 2 months of age unless directed by the patient's doctor because sulfonamides may cause serious unwanted effects.

Sulfonamides are best taken with a full glass (8 ounces) of water. Several additional glasses of water should be taken every day, unless otherwise directed by your doctor. Drinking extra water will help to prevent some unwanted effects of sulfonamides.

For patients taking the oral liquid form of this medicine:

Use a specially marked measuring spoon or other device to measure each dose accurately. The average household teaspoon may not hold the right amount of liquid.

To help clear up your infection completely, keep taking this medicine for the full time of treatment, even if you begin to feel better after a few days. If you stop taking this medicine too soon, your symptoms may return.

This medicine works best when there is a constant amount in the blood or urine. To help keep the amount constant, do not miss any doses. Also, it is best to take the doses at evenly spaced times day and night. If you need help in planning the best times to take your medicine, check with your health care professional.

Dosing

The dose medicines in this class will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of these medicines. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

For sulfadiazine

For oral dosage form (tablet):

For bacterial or protozoal infections:

Adults and teenagers—2 to 4 grams for the first dose, then 1 gram every four to six hours.

Children 2 months of age and older—Dose is based on body weight. The usual dose is 75 milligrams (mg) per kilogram (kg) (34 mg per pound) of body weight for the first dose, then 37.5 mg per kg (17 mg per pound) of body weight every six hours, or 25 mg per kg (11.4 mg per pound) of body weight every four hours.

Children up to 2 months of age—Use is not recommended.

For sulfamethizole

For oral dosage form (tablets):

For bacterial infections:

Adults and teenagers—500 milligrams (mg) to 1 gram every six to eight hours.

Children 2 months of age and older—Dose is based on body weight. The usual dose is 7.5 to 11.25 mg per kilogram (kg) (3.4 to 5.1 mg per pound) of body weight every six hours.

Children up to 2 months of age—Use is not recommended.

For sulfamethoxazole

For oral dosage form (tablets):

For bacterial or protozoal infections:

Adults and teenagers—2 to 4 grams for the first dose, then 1 to 2 grams every eight to twelve hours.

Children 2 months of age and older—Dose is based on body weight. The usual dose is 50 to 60 milligrams (mg) per kilogram (kg) (22.7 to 27.3 mg per pound) of body weight for the first dose, then 25 to 30 mg per kg (11.4 to 13.6 mg per pound) of body weight every twelve hours.

Children up to 2 months of age—Use and dose must be determined by your doctor.

For sulfisoxazole

For oral dosage forms (suspension, syrup, or tablets):

Adults and teenagers—2 to 4 grams for the first dose, then 750 milligrams (mg) to 1.5 grams every four hours; or 1 to 2 grams every six hours.Children 2 months of age and older—Dose is based on body weight. The usual dose is 75 mg per kilogram (kg) (34 mg per pound) of body weight for the first dose, then 25 mg per kg (11.4 mg per pound) of body weight every four hours, or 37.5 mg per kg (17 mg per pound) of body weight every six hours.Children up to 2 months of age—Use and dose must be determined by your doctor.

Adults and teenagers—2 to 4 grams for the first dose, then 750 milligrams (mg) to 1.5 grams every four hours; or 1 to 2 grams every six hours.

Children 2 months of age and older—Dose is based on body weight. The usual dose is 75 mg per kilogram (kg) (34 mg per pound) of body weight for the first dose, then 25 mg per kg (11.4 mg per pound) of body weight every four hours, or 37.5 mg per kg (17 mg per pound) of body weight every six hours.

Children up to 2 months of age—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Keep out of the reach of children.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.